This invention relates generally to compositions for disinfecting substrates as well as to processes for preparing and using such compositions.
The term "disinfectant" is used in this specification to broadly include any substance or composition that disinfects, sanitizes, deodorizes, sterilizes, or kills germs.
The use of chlorine compounds in various types of disinfectant compositions is well known. Chlorine compounds suggested for use in this regard include, for example, sodium hypochlorite, used in World War I as a wound irrigant, and chlorinated phenols, such as m-chlorophenol. These compounds have increased bactericidal activity and reduced toxicity, in some instances, when compared to non-chlorinated phenols. Thus, m-chlorophenol has a phenol coefficient of 5.9 (S. aureus) to 7.4 (B. typhosus). Other chlorine compounds having some form of disinfectant utility include, for example, chlorine gas itself, chlorine dioxide, chloramine T, calcium hypochlorite (a standard swimming pool disinfectant), chloropicrin (a larvicide), chloroform (a fumigant), chlordane (an insecticide), and chloromycetin (an antibiotic).
Chlorine dioxide in particular has been found to be an especially effective disinfectant. This compound is quite versatile and has long been used as a bleaching agent such as in the oxidizing of the natural colorant present in cotton, wood pulp and other cellulosic fibrous material. In such uses, chlorine dioxide, though performing an oxidizing function, is nevertheless non-injurious with respect to the fibrous material.
Particularly useful disinfecting compositions which employ chlorine containing compounds are disclosed in U.S. Pat. Nos. 4,330,531 and 4,585,482. These compositions comprise chlorite salts, such as sodium chlorite, in combination with weak organic acids, such as lactic acid, to provide particularly effective disinfectant compositions. These compositions are useful in topically treating skin diseases such as acne and in toothpastes.
One particularly prevalent disease is mastitis in dairy herds. Mastitis is a highly infectious disease which affects the bovine udder. The losses in dairy production resulting from this disease are staggering. For example, in the United States alone, these losses are estimated to be in the hundreds of millions of dollars. Mastitis not only reduces the production of higher yielding animals, but also shortens their productive life.
It is well known that mastitis is transmitted from animal to animal. It has also been established that the only route of transmission of the disease is through the teat orifice. Conditions which are held primarily responsible for the high incidence of mastitis include poor udder hygiene and physical damage to the teats. Dairymen and veterinarians have long sought a conditioning and protective composition which is economical and also provides facility of use. A composition which would improve the normal condition of the udder and teats and would also aid in preventing or effectively reducing the incidence of mastitis would serve to substantially increase both the production and productive life of a dairy herd.
Infectious mastitis is caused by microorganisms. Prior art treatments, such as the use of sulfanilimide, have been only partially effective in controlling the disease because such treatments are useful against only one type of microorganism which causes mastitis but are not useful against other types. Since the infection is usually of a mixed character, it follows that the effectiveness of drugs such as sulfanilimide is limited for all practical purposes.
It has also been suggested to use penicillin for the treatment of mastitis. The use of this compound is not desirable, however, in view of the high cost and extraordinary conditions necessary for the preservation and use of penicillin.
It has been proposed in U.S. Pat. No. 3,222,252 to treat mastitis with a preparation which comprises a blend of edible, semi-drying oils and drying oils together with a fatty acid ester, skin emollient, film forming agent. It is said that the presence of a drying oil in the preparation is essential to provide the desired film forming property. But for the most part, these film forming based treatments of mastitis have been unsuccessful. The use of iodine and peroxide in conjunction with latex emulsion films has led to other problems, including milk contamination and skin irritation.
The use of compositions comprising metal chlorite and a weak organic acid such as lactic acid, are disclosed in U.S. Pat. No. 4,330,531. A chlorine dioxide releasing compound offers to substantially alleviate the problems associated with the prevention of mastitis. For this application, the use of a gelling agent to generate a viscous topical gel is essential. The viscosity is needed for proper adhesion to the skin surface for an extended length of time.
Past attempts to create a useful viscous topical gel containing chlorine dioxide releasing compounds have been less than completely successful. Of the gelling agents tried, none combined the properties needed for substantial effectiveness. Carbohydrate based gels lose their viscosity at higher pH's as the alkaline chlorites break down the long polymer chains. Inorganic thickeners, such as bentonite clays, participate in the reaction between the acid and chlorite, and tend to form stringy, unsuitable gels.
The search has continued for a viscous topical gel composition capable of embodying alkaline chlorites for the treatment and prevention of skin disease, infection and irritation on humans and other animals. This invention was made as a result of that search.